Over the years I’ve introduced several people to the Tommy Westphall Multiverse, and it never fails to generate a good conversation. It’s a way of understanding the interconnections between TV shows, and also lends insight into the creative process, especially in-jokes, of the people who work in the television industry. In essence, the Tommy Westphall Multiverse is a thought exercise, a parlor game writ large. And it’s tailor made for pop culture obsessives.

The starting point for any explanation of the Tommy Westphall Multiverse begins with a specific episode of a specific television show. That episode would be the final episode of the 1980s TV series St. Elsewhere, in which the show’s producers pulled an incredibly audacious trick on the audience.

I can’t remember if I watched that episode when it first ran or not. I probably did not, because the episode first ran on my 18th birthday—May 25, 1988. I seriously doubt that I was watching St. Elsewhere that night. I suppose I heard about the episode a little bit later.

In the very final scene of the episode, and thus of the series, there is an abrupt change in tone. We find ourselves in a working-class apartment—the familiar Dr. Donald Westphall enters, but—he’s wearing a hard hat; odd—and there’s Dr. Daniel Auschlander, sitting in a wing chair reading a newspaper, watching over Dr. Westphall’s—if he is indeed a doctor?—autistic son Tommy. Through the dialogue it is revealed that Auschlander is actually Westphall’s father—and thus the grandfather of autistic Tommy. Tommy keeps fiddling with a large snow globe, and his dad expresses some frustration that he can’t enter into the mental link his son has created with it. Eventually he takes the snow globe out of his son’s hands and places it on a countertop—after which the camera zooms in relentlessly on the snow globe, revealing the familiar contours of the St. Eligius Hospital inside, familiar to its fans via the show’s opening credits.

“Whaaaaaaaaaaaaaaaaaaaaat?” you can still hear the show’s fans crying in unison. Are you saying that the entire plot of the show was all just the fractured projections of an autistic mind? I can hardly think of a bleaker, nastier jape ever perpetrated on a major television network. Dallas may have erased a season via the old “it was a dream” maneuver—but the entire series? St. Elsewhere may have had a modest following for network TV of the 1980s, but that’s still several million people. The audacity of the parting shot could hardly be more profound.

And thus we can begin to ask the most important question of the Tommy Westphall Multiverse—Who is in the snow globe? Obviously all of the beloved characters on St. Elsewhere are in the snow globe—Dr. Craig, Dr. Ehrlich, Dr. Wayne Fiscus, Dr. Auschlander, and all of the rest of them—they’re all in the snow globe.

The Tommy Westphall Snow Globe!!

The creation of the Tommy Westphall Multiverse came about because of efforts to figure out certain connections—crossovers, let’s call them—between the characters of Homicide: Life on the Street and other programs, especially Law & Order. At some point those crossovers led to St. Elsewhere, and it was only a matter of time before someone realized that—if the characters of Homicide and Law & Order are in the same universe as St. Elsewhere, then that means that Lenny Briscoe, Jack McCoy, Claire Kincaid, Dr. Emil Skoda, Robert Goren, Olivia Benson, Meldrick Lewis, Frank Pembleton, Tim Bayliss and on and on—they’re also in the Tommy Westphall Snow Globe!

But we’re just getting started.

Because of the many opportunities television affords for (a) cross-promotion, (b) spin-offs, and (c) in-jokes, there are literally dozens and dozens of shows in the Tommy Westphall Snow Globe. The entire L&O universe is in there, but that also means that all of The Wire is in there too—keep in mind that John Munch popped up on an episode of The Wire......

The more you look at the Tommy Westphall Multiverse, the more fascinating it gets. Personally, I can look at this chart for 20 minutes at a time before getting tired of it. You know who else is in the Snow Globe? Darrin Stephens from Bewitched, Fred Mertz from I Love Lucy, Radar O’Reilly from M*A*S*H, Captain Picard from Star Trek: The Next Generation, and Devon Miles from Knight Rider. It seems incredible, but it’s true. That’s quite a fertile imagination that little autistic kid had!

Part of the fun is tracking how the links have been forged over time. Sometimes it’s in the form of a blatant cross-promotion—a character from Friends appearing on 30 Rock, for instance. But many of the links derive from playful homages that don’t require the consent of the party being celebrated. For instance, quoting now from the Multiverse’s all-important “Key,” which explains the connections, in this case how The X-Files got in: “The fictional car rental company Lariat where Mulder & Scully always rented their cars was featured prominently on the Veronica Mars episode ‘Rat Saw God.’”

I could say so much more, but the fun is in exploring the Multiverse on one’s own. And before you ask: No, Breaking Bad isn’t in the Multiverse, and neither is Mad Men. But give it time…..